Charles Edward Stuart (Bonnie Prince Charley a.k.a. The Young pretender) with an army of 4,000, mainly incorporating highland clans with some regular Irish/French troops. Charles was Italian by birth and new little about 'his people' he was a brave man but had limited military experience. His greatest mistakes were to ignore his ablest Commander Lord George Murray in favour of less able counsel.
William Augustus, The Duke Of Cumberland later known among the Scots as 'Butcher' with an army of 9,000 troops, mainly well equipped English regiments but also lowland Scots and Highlanders, more Scots in fact than are with Charles. Cumberland was an imposing figure, being 16st (224 pounds) but was an experienced commander and well liked by his own troops.
The Jacobites had little artillery and only a few cavalry. The only real tactic open to the army was the highland charge, which had previously routed mainly raw Government troops. At Culloden however the Prince had allowed the battle to take place on ground totally unsuitable for this tactic.
In addition the Government troops had been drilled in a new tactic which effectively stopped the Highland charge and introduced a new and deadly weapon, the bayonet.
The result was complete the defeat of the Prince and his army.